OPERATING INSTRUCTIONS FOR LXT-220. Dissolved Oxygen Controller DANGER

Transcription

1 OPERATING INSTRUCTIONS FOR LXT-220 Dissolved Oxygen Controller P/N Mxxxxx ECO: DANGER Toxic gases and or flammable liquids may be present in this monitoring system. Personal protective equipment may be required when servicing this instrument. Hazardous voltages exist on certain components internally which may persist for a time even after the power is turned off and disconnected. Only authorized personnel should conduct maintenance and/or servicing. Before conducting any maintenance or servicing, consult with authorized supervisor/manager. Teledyne Analytical Instruments

2 LXT-220 DO Copyright 2005 Teledyne Instruments/ Analytical Instruments All Rights Reserved. No part of this manual may be reproduced, transmitted, transcribed, stored in a retrieval system, or translated into any other language or computer language in whole or in part, in any form or by any means, whether it be electronic, mechanical, magnetic, optical, manual, or otherwise, without the prior written consent of Teledyne Instruments/ Analytical Instruments, Chestnut Street, City of Industry, CA Warranty This equipment is sold subject to the mutual agreement that it is warranted by us free from defects of material and of construction, and that our liability shall be limited to replacing or repairing at our factory (without charge, except for transportation), or at customer plant at our option, any material or construction in which defects become apparent within one year from the date of shipment, except in cases where quotations or acknowledgements provide for a shorter period. Components manufactured by others bear the warranty of their manufacturer. This warranty does not cover defects caused by wear, accident, misuse, neglect or repairs other than those performed by TI/AI or an authorized service center. We assume no liability for direct or indirect damages of any kind and the purchaser by the acceptance of the equipment will assume all liability for any damage which may result from its use or misuse. We reserve the right to employ any suitable material in the manufacture of our apparatus, and to make any alterations in the dimensions, shape or weight of any parts, in so far as such alterations do not adversely affect our warranty. Important Notice This instrument provides measurement readings to its user, and serves as a tool by which valuable data can be gathered. The information provided by the instrument may assist the user in eliminating potential hazards caused by his process; however, it is essential that all personnel involved in the use of the instrument or its interface, with the process being measured, be properly trained in the process itself, as well as all instrumentation related to it. The safety of personnel is ultimately the responsibility of those who control process conditions. While this instrument may be able to provide early warning of imminent danger, it has no control over process conditions, and it can be misused. In particular, any alarm or control systems installed must be tested and understood, both as to how they operate and as to how they can be defeated. Any safeguards required such as locks, labels, or redundancy, must be provided by the user or specifically requested of TI/AI at the time the order is placed. Therefore, the purchaser must be aware of the hazardous process conditions. The purchaser is responsible for the training of personnel, for providing hazard warning methods and instrumentation per the appropriate standards, and for ensuring that hazard warning devices and instrumentation are maintained and operated properly. Teledyne Instruments/ Analytical Instruments, the manufacturer of this instrument, cannot accept responsibility for conditions beyond its knowledge and control. No statement expressed or implied by this document or any information disseminated by the manufacturer or its agents, is to be construed as a warranty of adequate safety control under the user s process conditions. Teledyne Analytical Instruments ii

3 Dissolved Oxygen Controller Specific Model Information Instrument Serial Number: Instrument Range: Calibrated for: Teledyne Analytical Instruments iii

4 LXT-220 DO Safety Messages Your safety and the safety of others is very important. We have provided many important safety messages in this manual. Please read these messages carefully. A safety message alerts you to potential hazards that could hurt you or others. Each safety message is associated with a safety alert symbol. These symbols are found in the manual and inside the instrument. The definition of these symbols is described below: GENERAL WARNING/CAUTION: Refer to the instructions for details on the specific danger. These cautions warn of specific procedures which if not followed could cause bodily Injury and/or damage the instrument. CAUTION: HOT SURFACE WARNING: This warning is specific to heated components within the instrument. Failure to heed the warning could result in serious burns to skin and underlying tissue. WARNING: ELECTRICAL SHOCK HAZARD: Dangerous voltages appear within this instrument. This warning is specific to an electrical hazard existing at or nearby the component or procedure under discussion. Failure to heed this warning could result in injury and/or death from electrocution. Technician Symbol: All operations marked with this symbol are to be performed by qualified maintenance personnel only. No Symbol NOTE: Additional information and comments regarding a specific component or procedure are highlighted in the form of a note. CAUTION: THE ANALYZER SHOULD ONLY BE USED FOR THE PURPOSE AND IN THE MANNER DESCRIBED IN THIS MANUAL. Teledyne Analytical Instruments iv

5 Dissolved Oxygen Controller IF YOU USE THE ANALYZER IN A MANNER OTHER THAN THAT FOR WHICH IT WAS INTENDED, UNPREDICTABLE BEHAVIOR COULD RESULT POSSIBLY ACCOMPANIED WITH HAZARDOUS CONSEQUENCES. This manual provides information designed to guide you through the installation, calibration operation and maintenance of your new process controller. Please read this manual and keep it available. Occasionally, some instruments are customized for a particular application or features and/or options added per customer requests. Please check the front of this manual for any additional information in the form of an Addendum which discusses specific information, procedures, cautions and warnings that may be peculiar to your instrument. Manuals do get lost. Additional manuals can be obtained from TI/AI at the address given in the Appendix. Some of our manuals are available in electronic form via the internet. Please visit our website at: Teledyne Analytical Instruments v

6 LXT-220 DO Table of Contents List of Figures... ix List of Tables... x Introduction Overview Main Features of the Transmitter Optional Features Front Panel Internal Connections 17 Installation Unpacking the Instrument Mounting Electrical Connections AC Power Sensor Wiring Configuring the LXT Calibration 22 Operation Using the Front Panel Keys Menu Selection Keys Calibrate Keys Menus Contrast Main Menu Output Graph Parameter Selection Menu Calibration Submenu 27 Teledyne Analytical Instruments vi

7 Dissolved Oxygen Controller Setup Submenu Status Menu Exit/Stay Menu Configuring the LXT Password Protection Changing Protection Level Changing Operational Password Changing Configuration Password ma Output Assignments Manual Mode Assignment HART Output Assignments Relay Assignments Temperature Calibration Trim Input A/D Converter Trim PID Assignments Calibration Manual Output Mode Parameter Selection Menu Buffer Menu One-Point Buffer Calibration (Standardize) Two-Point Buffer Calibration (Span) Calibration Using a Grab Sample as a Standard Calibration Error Detection & Electrode Operational Guidelines Back-to-Factory Calibration 49 Maintenance Routine Maintenance Cleaning Replacement of the Microprocessor: 51 Appendix...53 A.1 Specifications 53 Teledyne Analytical Instruments vii

8 LXT-220 DO A.4 Model Designation 55 Index Teledyne Analytical Instruments viii

9 Dissolved Oxygen Controller List of Figures Figure 1-1: LXT-220 Front Panel...16 Figure 1-2: Internal Layout of the LXT-220 DO Controller...17 Figure 2-1: Opening the Front Panel...20 Figure 2-2: LXT-220 Electrical Connections...21 Figure 3-1: Available Menus and Submenus...25 Figure 3-2: Numerical Entry Using Front Panel Keys...32 Teledyne Analytical Instruments ix

10 LXT-220 DO List of Tables Table 3-1: Protection Level Exceptions Table 4-1: Troubleshooting Teledyne Analytical Instruments x

11 Dissolved Oxygen Controller This is a general purpose instrument designed for liquid measurements in a non-hazardous area. It is the customer's responsibility to ensure safety especially when hot or flammable liquids are being analyzed since the potential of leaks always exist. The customer should ensure that the principles of operating this equipment are well understood by the user. Misuse of this product in any manner, tampering with its components, or unauthorized substitution of any component may adversely affect the safety of this instrument. Since the use of this instrument is beyond the control of Teledyne Instruments/ Analytical Instruments, referred as TI/AI, no responsibility by TI/AI, its affiliates, and agents for damage or injury from misuse or neglect of this equipment is implied or assumed. Teledyne Analytical Instruments xi

12 LXT-220 DO Teledyne Analytical Instruments xii

13 Dissolved Oxygen Controller Introduction Introduction 1.1 Overview Teledyne s Model LXT-220 Dissolved Oxygen Controller is a robust and versatile instrument for the measurement and process control of dissolved oxygen in a liquid component. Highly customizable, the Model LXT-220 comes standard with a single 4-20mA current output but can have as many as five. The current output is field selectable and may be expanded to any range within the transmitter s full operating range. It can also be programmed as reverse acting; for example, a 4-20 ma output for a range of 0 to 10 ppm can be reversed to 10 to 0 ppm. The standard instrument accepts a single input typically from a Teledyne SP1 or SP2 Dissolved Oxygen probe however a dual input option is available. This optional dual input extends the functionality of the instrument to accept conditioned input from a variety of sensors for specific process measurements such as: Second Dissolved Oxygen (DO) channel Resistivity/conductivity ph Oxidation-Reduction Potential (ORP) Specific Ion For process control, the microprocessor based LXT-220 Transmitter employs a multi-bus system architecture for PID temperature control and sensor-specific process variable outputs such as DO, ph, ORP, Resistivity/Conductivity, and ion-specific element (ISE) output as a function of multiple inputs. Up to six field-configurable alarm or control relay outputs are available to the user to match individual process needs. These relays can be field configured as high or low alarms. Hysterisis (dead band) is defined by setting the ON and OFF relay values. These relays can be configured to any of the input parameters. (See Section 3.3.5). Teledyne Analytical Instruments 13

14 Introduction LXT-220 DO The LXT-220 can be upgraded with pre-phault Diagnostics & HART Communications option which alerts the operator to a pending DO, ph, ORP, or ISE electrode failure. The LXT-220 is housed in a rugged NEMA-4X housing with all operator switches conveniently located on the front panel. 1.2 Main Features of the Transmitter The LXT-220 Controller for dissolved oxygen applications incorporates the following standard features: Front panel membrane switches Menu driven backlit display with contrast adjustment Automatic Calibration. This allows calibration points to be defined upon initialization of the transmitter. An easy back to factory calibration menu allows the instrument to return to a predetermined factory calibration. The default parameters are: zero electrode offset and 157.5mV/FS slope. 4-20mA current output fully expandable to any range within the transmitter s full operating range. The output is field selectable and fully programmable. The current output can be configured to be reverse acting. Temperature Conversion. Temperature can be displayed in either Fahrenheit or Celsius. The units can be toggled from one to the other in the field with the conversion calculation performed automatically. 1.3 Optional Features The Model LXT-220 DO Controller is a versatile instrument designed to meet the needs for liquid analytics and process control across a wide range of applications. There are many options available for the transmitter including: Dual Input: An optional second input can be provided for ph, ORP, resistivity/conductivity, or Specific Ion. The second input can also be used as a second analysis for dissolved oxygen or as specific compensation for the primary input. Teledyne Analytical Instruments 14

15 Dissolved Oxygen Controller Introduction PID Output: An optional PID output is available and provides a 4-20 ma, three-mode control signal. Proportional band is adjustable from 0.1 to 1,000%. Reset and Rate are adjustable from 0.00 to 100 repeats per minute and 0.00 to 1,000 minutes, respectively. The PID output can be assigned and configured to any of the available outputs. Multiple Output: The standard LXT-220 DO Controller is provided with a single output. With the multiple output option, up to four additional outputs can be added. These outputs can be defined in the field as the process variable (DO, ph, ORP, resistivity, conductivity), temperature, or PID. The additional outputs are fully isolated from the inputs and the primary output and are "floating" so they can have either a positive or negative common. Note: These isolated outputs are floating and require an external 24 VDC power source to operate. TI/AI can supply an internal 24 VDC power supply to power these outputs. Contact the factory for additional information. Alarm Relays: Up to six alarm or control relays are available for the primary channel, or divided between the two channels on dual output transmitters. Relay outputs can be field configured as high or low alarms. Hysteresis (dead band) is defined by setting the "ON" and "OFF" relay values. The relays can be configured to any of the input parameters. HART Output: This option provides both digital and analog outputs that is useful for monitoring and controlling process variables in a multiple output instrument. Optional Software Differential Output: Provides an output expressed as the difference between two inputs. Ratio Output: Provides an output expressed as the ratio of two inputs. This is applicable to percent rejection in some applications. Averaged Output: Provides an output expressed as the average of two inputs. Teledyne Analytical Instruments 15

16 Introduction LXT-220 DO 1.4 Front Panel The operator interfaces with the instrument from the front panel. Figure 1-1 shows a standard single channel LXT-220 DO instrument front panel. The panel includes the LCD display capable of outputting information in both a textural and graphical format. There are 6 membrane switches (keys) that control the operation of the unit. The keys are in two groups: MENU SELECT: UP/DOWN ( / ) These keys are used to change the display menu and move the cursor vertically. Any menu can be accessed using the appropriate MENU SELECT key. These keys are also used to exit the calibration mode and save calibration data. CALIBRATE KEYS: UP/DOWN/LEFT/RIGHT ( / / / ) The horizontal CALIBRATE keys are used to enter the calibrate mode and move the cursor horizontally. To enter the calibrate mode, both horizontal CALIBRATE keys must be pressed simultaneously. Once in the calibrate mode, the cursor can be positioned by pressing the appropriate individual CALIBRATE key. These keys are also used to select an item from a menu. See Section 3.1) The vertical CALIBRATE keys are used to perform numeric adjustments to displayed values. Pressing the CALIBRATE key will increase the value; pressing the CALIBRATE key will decrease the value. Figure 1-1: LXT-220 Front Panel Teledyne Analytical Instruments 16

17 Dissolved Oxygen Controller Introduction 1.5 Internal Connections All user connections are made inside the unit on removable terminal blocks. Two conduit holes are provided on the NEMA-4X housing, one for low level DC signal and the other for 115VAC power wiring. Access to the terminal blocks is gained after removing the 4 captive jackscrews on the front of the instrument. Figure 2 shows the internal layout of the LXT-220 Controller. A label on the enclosure cover shows the terminal block arrangement for all the wiring along with the model number and the factory assignment of the output signals. These can be changed in the field if the application prefers a different arrangement. Figure 1-2: Internal Layout of the LXT-220 DO Controller Teledyne Analytical Instruments 17

18 Introduction LXT-220 DO Teledyne Analytical Instruments 18

19 Dissolved Oxygen Controller Installation Installation Installation of the LXT-220 Controller involves: Unpacking the instrument Mounting Making Electrical Connections Configuring the Instrument Calibration 2.1 Unpacking the Instrument The LXT-220 Controller has been carefully packaged to protect it from damage during shipment and dry storage. Upon receipt please follow the procedure outlined below: 1. Before unpacking, inspect the condition of the shipping container to verify proper handling by the carrier. If damage is noted, save the shipping container as proof of mishandling for the carrier. 2. Check the contents of the shipping container with the items and quantities shown on the packing list. Immediately report any discrepancies to TI/TAI. 3. Save the original packing material until you are satisfied with the contents. In the event the transmitter must be returned to the factory, the packing material will allow you to properly ship it to TI/TAI. 4. Familiarize yourself with the instrument before installation, and follow proper installation and wiring procedures. 2.2 Mounting Three typical installation configurations are available for the LXT- 220: Universal mounting plate Teledyne Analytical Instruments 19

20 Installation LXT-220 DO Handrail mounting plate Panel mounting configurations. U-bolts may be ordered separately. Refer to the following application drawings for mounting details: Dimensions, wall & pipe mounting. The unit is supplied with a universal-mounting bracket. Two slots on each side will accommodate U-Bolts for pipe mounting Dimensions, Panel Mounting. This installation uses 1/4" screws. Panel mounting is accommodated using the captive jackscrew that will cinch the instrument bezel against the panel Dimensions, handrail mounting. These application drawings can be located in the back of this manual. 2.3 Electrical Connections All electrical connections are made with connectors to a panel inside the NEMA-4X enclosure. To gain access to the panel, use a flatblade screwdriver to remove the 4 captive screws on the front of the instrument and swing the panel out. See Figure 2-1. Figure 2-1: Opening the Front Panel Teledyne Analytical Instruments 20

21 Dissolved Oxygen Controller Installation AC Power The LXT-220 requires a 115 VAC 60 Hz power source. A 24VDC unit is available as an option. CAUTION: MAKE SURE THE CIRCUIT BREAKER PROTECTING THE AC INPUT LINE IS OFF BEFORE WIRING THE LXT-220. Application drawing illustrates the proper power wiring for single channel LXT-220 as does the affixed label on the backside of the front panel. The wires are best fed through the right conduit as shown in Figure Sensor Wiring Figure 2-2: LXT-220 Electrical Connections A conditioned input is required from the sensor or electrode to the LXT-220 for proper operation. Teledyne s SP1 and SP2 sensors will provide the required conditioning. The application drawing Teledyne Analytical Instruments 21

22 Installation LXT-220 DO illustrates the proper sensor wiring and is also shown on the affixed label on the backside of the front panel. 2.4 Configuring the LXT-220 The LXT-220 Controller is used for measurement and control for a wide range of liquid analytical applications. This manual describes the configuration for use in dissolved oxygen measurement and control applications. If your instrument included optional features such as dual channel input for handling other specific measurement processes, a second manual will be included to describe the setup and operational parameters specific to that function. Configuring the instrument is described in Section 3 of this manual. 2.5 Calibration Prior to using the instrument for the first time, the LXT-220 must be calibrated. The specific calibration procedure used depends on the application. Among other things, the calibration routine establishes the correspondence between the 4-20mA output signal and the application dependant measurable parameter. This manual describes operation for dissolved oxygen measurements and process control for the LXT-220. Calibration can be performed without disturbing control or recorder functions using a manual output mode (see Section 3.4.1). Typically, the calibration is done using either a one point buffer calibration (standardization) or two point (span) calibration. There is also a Back to Factory calibration feature which resets the LXT-220 to typical electrode for electrode potentials. As the electrode ages it will deteriorate and the mv/fs will decay and eventually require replacement. If the membrane is torn or coated the calibration will be either sluggish or out of range. This feature restores the instrument to the predetermined factory calibration point of zero electrode offset and mv/fs quickly. The calibration routines require a familiarity with the instrument operation and is described after fundamental operational parameters are discussed in Section 3. Teledyne Analytical Instruments 22

23 Dissolved Oxygen Controller Operation Operation No one instrument has all the options described in this document. Some options must be specified at the time the instrument is purchased, and are not field-alterable. The instrument can be returned to the factory for re-programming if your requirements change. 3.1 Using the Front Panel Keys Cursor positions or numeric adjustments are performed by pressing the appropriate keypad. The LXT-220 uses an "underscore" cursor in each of the menus. Holding down the keypad will automatically scroll the cursor or numeric values. Note: Simultaneous pressing both vertical keys or any combination of keys other than the two horizontal CALIBRATE keys is not recommended Menu Selection Keys The MENU SELECTION keys are used to: 1. Change the display menu and move the cursor vertically. Any menu can be accessed by the use of the appropriate up or down MENU SELECTION key. 2. Exit the calibration mode and save calibration data Calibrate Keys 1. The horizontal CALIBRATE keys are used to enter the calibrate mode and move the cursor horizontally. To enter the calibrate mode, both horizontal CALIBRATE keys must be pressed simultaneously. 2. Once in the calibrate mode, the cursor can be positioned by pressing the individual right-hand or left-hand horizontal CALIBRATE keys. Teledyne Analytical Instruments 23

24 Operation LXT-220 DO 3. With the cursor on a user selectable menu item, for instance SETUP in the Parameter Selection Menu, pressing both horizontal CALIBRATE keys will take you to the next lower level of screens: 4-20 ma screen, Relay Setup screen, etc. 4. The vertical CALIBRATE keys are used to perform numeric adjustments to displayed values. To use these keys, the LXT- 220 must be in the calibrate mode. Pressing the upper ( ) CALIBRATE key will increase the value; pressing the lower ( ) CALIBRATE key will decrease the value. To exit the calibrate mode, press either of the MENU SELECTION keys. 3.2 Menus The LXT-220 contains a series of menus and submenus from which different functions can be accessed. Even though the display only shows 4 menus per screen, you can scroll through all available menus by using the MENU SELECT and keys. The menus available in the standard LXT-220 instrument configured for single channel dissolved oxygen controllers are shown in Figure 3-1. When the instrument is first powered up, a copyright display will appear for a few seconds. This screen displays the serial number and software version for your instrument. After a few seconds the display changes to the main menu. From the main menu, you can scroll up ( ) to the contrast menu or down ( ) through the available menus for your controller. S/N 1004 V 1.00 (C)TI/TAI 2002 Copyright Display Some menus allow you to choose from several options. To select an option or item, scroll to the option using the MENU SELECT / keys. When the cursor is next to the item of interest select the item by simultaneously pressing both the left and right ( / ) CALIBRATE arrow keys on the right side of the front panel. Teledyne Analytical Instruments 24

25 Dissolved Oxygen Controller Operation There may be additional menus not shown in Figure 3-1 depending on the options you selected. Figure 3-1: Available Menus and Submenus In this manual, screens with a gray background are related to dissolved oxygen measurement or control while white background screens relate to a second channel process, for instance, ORP related screens. When there is only one gray screen the information applies to both process applications, for example, the contrast screen discussed next adjusts the contrast for all screens Contrast Display contrast can be adjusted to allow for variations of ambient lighting and viewing angle by using this menu. The Contrast Menu is the same for all LXT-220 controllers and is always located as the uppermost menu. To access this menu from the Main Menu, press the MENU SELECT key. Contrast 50 Contrast Menu Teledyne Analytical Instruments 25

26 Operation LXT-220 DO Procedure: 1. Press the upper MENU SELECTION key to reach the Contrast Menu. 2. Press both horizontal CALIBRATE keys simultaneously to enter the calibrate mode. Observe the cursor move to the last digit. 3. Using the horizontal CALIBRATE keys, position the cursor under the digit to be adjusted. 4. Increase or decrease the value by pressing the appropriate vertical CALIBRATE key. 5. To save the contrast value and exit the calibrate mode, press either MENU SELECTION key Main Menu This menu appears after the copyright display when power is first applied to the LXT-220. The MAIN MENU displays the measured process variable, temperature, and the current output in percent of fullscale. While in this menu, the current output can be adjusted and locked in a manual mode to provide an undisturbed output during sensor calibrations. The screens below are for a two-channel instrument. To access the following menus in a two-channel instrument scroll down for channel 1 and scroll up for channel 2. For a single channel instrument scrolling down accesses all menus. 2 DO % 25.0 O C 1 DO % 25.0 O C Main Menu, ph 2 ORP % 25.0 O C Main Menu, ORP Output Graph This screen graphically displays the output current that is set up in the Main screen. The X-axis of the graph display is factory set to ~150 samples 6 sec or.1min/sample). The setup screen sets the Y-axis (the sensitivity). If the graph were assigned to a current output the sensitivity would be that of the 4 to 20 ma output. Teledyne Analytical Instruments 26

27 Dissolved Oxygen Controller Operation Graph Parameter Selection Menu Buffer Setup Status This menu allows you to select what function you would like to perform. With the cursor on BUFFER, if you press and together the LXT-220 will enter the calibration menus (standardize and span). Scrolling to and choosing SETUP brings you to where you can configure and setup the instrument. The STATUS section allows the user to view the calibration engineering data (mv input from the sensor and the zero potential from the last cal). Each section is entered by placing the cursor under the first letter of the section you wish to enter and pressing the two horizontal calibrate keys simultaneously. The Parameter Selection Menu is discussed in detail in Section CALIBRATION SUBMENU Parameter Selection Menu Choosing BUFFER from the Parameter Selection Menu brings up a submenu that allows the user to perform a 1 or 2 point buffer calibration (standardize & span). This menu is described in detail in Section Calibration. 1 DO.00 ppm Cal.0 mv Zero Calibration Menu DO Teledyne Analytical Instruments 27

28 Operation LXT-220 DO SETUP SUBMENU Choosing SETUP from the Parameter Selection Menu brings up the first of a series of screens that allows the user to configure some initial parameters in the LXT-220 controller. These parameters are: 4 to 20 ma outputs relay contacts PID control HART You can also setup how the graphic display plots the current output using the Plot function. The menu below shows the Plot function. In this case, the process variable assigned to Channel 1 is plotted and sampled every 6 seconds (.1 min). Plot Sample.1 m (ch1 PV) Current output menu To set up additional parameters or to change to current preset parameters refer to Section 3.3 Configuring the LXT-220 in this manual CURRENT OUTPUT SETUP This menu is used to set or adjust the current output range with the process variable. The top line defines the 4 ma point, while the bottom line defines the 20 ma point. Between these points, the output current is linear with respect to the sensor input. The standard LXT-220 provides a single output channel but options are available to expand the number of current outputs to 4. See Section 3.3 Configuring the LXT-220 in this manual for information on assigning other parameters to additional outputs. 4mA1.00 ppm 20mA ppm (now ma) (ch1 PV) Current output menu Teledyne Analytical Instruments 28

29 Dissolved Oxygen Controller Operation RELAY CONTACTS Relay on/off set points are adjusted in this menu. The top line defines the point in which the relay is energized (on) and the bottom line defines the point in which the relay is de-energized (off). The LXT-220 can contain up to 6 sets of relay contacts. Refer to Section Relay Assignments to set up the number of contacts. 1 On > ppm 1. Off < 9.85 ppm (ch1 PV) Relay set up menu DO LOCUS AND NOISE FILTER SETTINGS The Locus is the temperature where the different concentrations are equal and is referenced for temperature compensation. The noise filter is adjustable from 1 to 20 to dampen any distracting fluctuations on the sensor DO Locus O C Noise filter 10 Electrode Data menu ORP Electrode Data menu ORP STATUS MENU This menu allows the user to view the time of day clock and the engineering information pertaining to the electrode as an informational screen only. The top line displays the real-time (active) absolute millivolt value (mva) the electrode is generating, uncompensated for temperature variations. The bottom line displays the electrode zero potential from the last calibration. This information is extremely helpful in determining the diagnostic status of an electrode. In conjunction with regular calibrations, the Electrode Diagnostic Screen provides valuable information to track electrode performance. Teledyne Analytical Instruments 29

30 Operation LXT-220 DO Fri 12:00:37 Input mva 0 mv.00ppm (volatile) Time of day clock Electrode Data menu ORP EXIT/STAY MENU This menu confirms that the user wishes to leave the section that they are currently in. This menu will show up each time that the LX- Exit Stay Exit / Stay menu 220 is prompted to leave the current section before it goes back to the parameter selection menu. Press the appropriate menu selection key either to stay in the current section or exit and return to the parameter selection menu. 3.3 Configuring the LXT-220 To initially configure or reconfigure the instrument, use the leftside and MENU SELECT keys to scroll to the bottom of the menus list and stop when the CONFIGURE/TRIM option is displayed. Simultaneously depress the and keys to enter the configuration mode. This mode should be password protected if access to the keyboard is unrestricted. The new configuration remains in effect through indefinite power outages. The configuration mode is a submenu grouping of 9 or more functions that can be set by the user to tailor the instrument to a particular application. The following 7 functions appear in groups of 4 for a standard instrument: PASSWORDS 4-20 ASSIGN 4-20 MANUAL MODE RELAY ASSIGN/TST C/ F & TEMP CAL 4-20 TRIM/TEST Teledyne Analytical Instruments 30

31 Dissolved Oxygen Controller Operation INPUT A/D CONVERTER TRIM Some instruments have two channels measuring two unrelated quantities, and in those cases both channels can be configured from the same configuration menus. Depending on options selected 2 additional submenus could appear: PID ASSIGN HART ASSIGN Scroll down to the item of interest, and then simultaneously depress the and keys to access the sub-menu for that item Password Protection It is worthwhile to become familiar with the password capabilities of the instrument even if you decide not to use them, as it is possible that one gets set by mistake and you need to change or erase it. Password protection can be selectively turned on for the operational and configuration displays. The operational and configuration passwords can be different. Passwords are entered using only the right four keys, and the passwords are numbers consisting only of the digits 1 to 4. No digits are shown on the keyboard. It is necessary to remember that the top key is 1, the right key is 2, the bottom key is 3, and the left key is 4. See Figure 3-2. Teledyne Analytical Instruments 31

32 Operation LXT-220 DO Figure 3-2: Numerical Entry Using Front Panel Keys After successfully entering the operational password it remains valid for 60 seconds after exiting the calibration mode on that display. During that time a second display can be accessed without re-entering the password. The 60 second timer starts again when exiting the calibration mode on that display also, so that any number of operational displays can be modified with a single password entry. If the wrong password is entered three consecutive times in accessing a protected display all password access is disabled, and the main display shows Err PW. The instrument continues to function normally, but none of the password-protected settings can be changed. Normal operation is restored by momentarily turning off power. No keyboard commands are required to restore normal password protection. The Err PW display is cleared by any keystroke, but when attempting to enter a password the display will still show disabled. If the password is lost and you want to gain access to protected screens and/or enter a new password, turn off the power, and then reapply it. Within one second of the time that text first appears on the screen, press the rightmost key on the keyboard. The screen will go blank to acknowledge the key press, but there will be no other visible indication that the key is recognized. After a few seconds the instrument will begin functioning normally except that the configuration password has been disabled for 60 seconds. The operational password remains in effect. Immediately enter the configuration mode and choose a new password. Note: This method will not work if the key is down at the time power is applied. The key must be depressed shortly after text first appears. The following displays control the password settings. Operate password level: 3 no PW Teledyne Analytical Instruments 32

33 Dissolved Oxygen Controller Operation The protection level for the operational displays is the number on the left side of the second line. None of the operational displays are password protected if the protection level is 0. If it is not zero then, with the exceptions shown in Table 3-1, all displays that affect the operation of the instrument are protected. An N entry in the table means that the display is not protected. Table 3-1: Protection Level Exceptions level contrast man out 1-point buf 1 N N N 2 Y Y N 3 Y N Y 4 Y Y Y CHANGING PROTECTION LEVEL To change the protection level, navigate using the right side (CALIBRATE) / keys to the old protection level number (3 in the above screen). Adjust the numerical value using the right side (CALIBRATE) / keys and then accept the input by pressing either of the left side MENU SELECT) / keys. The old operational password is erased if the protection level is changed to 0. Changing from 0 to another value has no effect until a new password is entered. The display shows no PW if the password has been erased CHANGING OPERATIONAL PASSWORD To enter a new operational password, navigate to the old password (or no PW) using the (CALIBRATE) / keys and select by pressing both (CALIBRATE) / keys simultaneously. This brings up the new operational password screen. New opr password Teledyne Analytical Instruments 33

34 Operation LXT-220 DO Press both (CALIBRATE) / keys again to enter a new operational password. 1 to 8 digits may he entered. Press either of the menu keys to accept the new password when done. Note: A new password will not be accepted unless the protection level has already been set to a value greater than CHANGING CONFIGURATION PASSWORD To change the configuration password, use the MENU SELECT / keys to navigate to the PASSWORD menu and select it by pressing both CALIBRATE / keys simultaneously. Use the MENU SELECT / keys to bring the cursor to the Configure password level screen. Config password level: 1 no PW To enter a new configure password, navigate to the old password (or no PW) using the (CALIBRATE) / keys and select by pressing both (CALIBRATE) / keys simultaneously. This brings up the new configure password screen. New opr password Press both (CALIBRATE) / keys again to enter a new configure password. 1 to 8 digits may he entered. Press either of the menu keys to accept the new password when done. Note: A new configure password will not be accepted unless the protection level has already been set to 1. These two displays work the same as the corresponding operational displays, except that the protection level can only be 0 or 1. Teledyne Analytical Instruments 34

35 Dissolved Oxygen Controller Operation The configuration password is rarely used and the configuration settings are more sensitive, so the password should use more digits than the operational password. With eight base 4 digits the odds of breaking the code in three tries are 3 in if the user knows that there are 8 digits. The user will not know the number of digits that you chose, so the odds are usually smaller than that. The maximum number of digits allowed in a password, or the number actually used, cannot be determined by entering trial passwords. A two or three digit password is therefore moderately effective if systematic attempts at breaking the code are not anticipated, but short passwords should nevertheless be avoided in a critical process ma Output Assignments The next group of displays are used to assign the 4-20 ma outputs. Note: The LXT-220 has been configured at the factory for your specific application as specified at the time of the order. Using the MENU SELECT / keys, scroll down to the 4-20 ma ASSIGN option and select it by pressing both CALIBRATE / keys simultaneously. The screen will display : where... is one of the following selections: missing unused ch1 PV ch1 temp ch1 PID ch2 PV ch2 temp ch2 PID not installed Installed but not currently used Channel 1 process value Channel 1 temperature Channel 1 PID controller output Channel 2 process value Channel 2 temperature Channel 2 PID controller output The channel 2 options are only shown on two channel instruments, and specialized instruments may show additional options. To change the output assignment, first push both CALIBRATE / keys, causing the cursor to move to the right. Then use the right-side CALIBRATE / keys to scroll through the list of options. The list is Teledyne Analytical Instruments 35

36 Operation LXT-220 DO cyclic. Use either of the MENU SELECT / keys to accept the selection and move the cursor back to the left. The displayed selection remains in effect until changed and the selection is remembered through power outages of indefinite length. Up to two 4-20 outputs can be assigned to the same source. There is no error indication if more than two are assigned to the same source, but there will be no span display for the third. A span display will otherwise be present in the main menu for each 4-20 output that is assigned to a source. If the source is associated with channel 2 then the span display will be in the channel 2 group. The new assignment is not functional until the setpoints in the span display are set. If a PID controller is selected as a source then its support displays will also be present. The next two displays are for the second and third 4-20mA outputs. Some units do not have all three outputs, but the displays will show three output options anyway, as the additional outputs can be retrofitted. The 'missing' assignment should be selected for uninstalled outputs. The software cannot determine how many 4-20 outputs are installed, so the 'missing' selection might not reflect the actual configuration. Output #4 is dedicated to HART, and its assignment is discussed in the HART section. If the instrument is not connected to a HART network then the fourth output can be used like any of the other outputs. The fourth output is only present if the instrument was purchased with the HART option. A span display will be present in the setup menu for each 4-20 output that is assigned to a source unless the source is a PID controller. PID controllers have different setup displays, and they are in the same section. If the source is associated with channel 2 then the display will be in the channel 2 group. The new assignment is not usable until the setpoints or PID parameters are specified in the operational displays. The third line of the display will show a line such as (ch1 man mode) if an assignable manual mode control is associated with the output. The line will begin with a question mark if making the current selection permanent would result in a manual mode assignment conflict. Refer to Section Manual Mode Assignment for more information Manual Mode Assignment In the manual output mode, the current output is manually set to the desired level and saved until changed or released from the manual mode. The main menu display shows the process value and a 4-20 ma percent Teledyne Analytical Instruments 36

37 Dissolved Oxygen Controller Operation output field for each channel. The manual mode assignment allows the percent output display to be associated with any of the 4-20 outputs, including the HART output. When in the manual mode the 4-20 output is controlled from the keyboard. Zero percent corresponds to a current of 4 ma, and 100 percent corresponds to a current of 20 ma. If a 4-20 output is used to control the process then the manual mode is normally assigned to that output, although the instrument does not require this choice. Cross-channel assignments are allowed in that the selected 4-20 can be assigned to something on the other channel. Cross-channel assignments can usually be avoided, and they should be avoided when possible. ch1 man mode on 4-20: 3 (ch1 PV) To change the assignment simultaneously depress both CALIBRATE / keys, then use the right-side CALIBRATE / keys to change the selection. One of the selections is none, and with that selection the percent output field is not present in the operational display. The bottom line shows the signal that the selected 4-20 is assigned to. On two channel instruments the next display is the manual mode assignment for channel two. Each 4-20 output can have only one manual mode control assigned to it. If one already exists for the current selection it will be preceded by a question mark. Some instruments have more than two manual mode controls in the operational displays, and they must all he assigned to different 4-20 outputs if they are activated. The other manual mode controls are built-in in some instruments. An example would he the weight-percent display of a conductivity unit. The manual mode field appears in a separate display in these cases, and it is independent of the manual mode assignments for the main display. The manual mode capability is automatically activated when a 4-20 is assigned to one of these functions. The percent output field does not appear in the operational display unless a 4-20 is assigned to it. Conversely, when changing the 4-20 assignments a conflict can arise if a 4-20 with a pre-existing manual mode control is reassigned to Teledyne Analytical Instruments 37

38 Operation LXT-220 DO a function with its own manual mode output. The 4-20 assignment display will show if the output is associated with an assignable manual mode. Regardless of the cause, the affected operational display manual mode fields will begin with a question mark when a conflict exists. When that happens refer to the manual mode configuration displays, and HART 1:.. the question marks there will show where the problem lies. No contention occurs unless two different displays are actually in the manual mode for the same 4-20, so the question marks in the displays can be ignored if the assignments are made for diagnostic purposes HART Output Assignments If the instrument was purchased with the HART option then the next five displays are for assigning the HART digital and analog outputs. The first of these displays is: where represents one of the items from the 4-20 ma assignment list in Section HART command #3 requests four variables from the instrument. Each of these variables can be assigned to any of the sources shown in the 4-20 assignment section. Each variable has a units code, which identifies the variable as being ph, millivolts, degrees C, etc. The units code is supplied automatically depending on the assignment and the instrument configuration. If command 3 is not used then only the first output assignment will be reported. If any output is assigned to missing or unused then that value will be reported as not a number, and the units field will be not used. HART analog 1: The first digital output assignment is referred to as the primary variable in the HART system. Teledyne Analytical Instruments 38

39 Dissolved Oxygen Controller Operation HART analog 2:, HART analog 3:, HART analog 4: The next three displays assign the second, third, and fourth variables. The assignments are changed in the same way as for the 4-20 outputs. See Section mA Output Assignments. It is not possible to assign more than one HART digital output to the same source. The current selection will be preceded by a < symbol on the display if making it permanent would result in duplication. HART analog: output #4 is dedicated to HART. This output normally carries the digital information superimposed on the 4-20 ma current. But if the HART system uses the multi-drop mode then the current output of 4-20 #5 is disabled, with only the digital signal remaining. Several instruments are connected in parallel in the multi-drop mode, so analog signaling is not possible. The current that would have been output is still reported digitally, as a percentage, and that will be sufficient for some applications. But if an actual 4-20 current is required then one of the other 4-20 outputs must be used to supply it, and this display is used to make the assignment. The specified 4-20 must in turn be assigned to an appropriate source. Note: If the HART analog output is assigned to an output other than #5, then #5 cannot be assigned to anything. It must be set to missing or unused. The span settings for the selected 4-20 output correspond directly to the HART lower and upper range limits, and they can be set either from the keyboard or with command #35. If they are changed with the command then the new value will be shown on the instrument's span display for the selected output. If they are changed from the keyboard then those values are reported digitally over the HART network. If command 35 is to be used to set the limits then the HART 4-20 output must be selected first because the output span does not exist until an assignment is made. The span settings must be readjusted or be resent when the HART analog output assignment is changed. The 4-20 supplying the HART analog output is normally assigned to the same source as the primary variable, and the HART displays show the engineering units for the upper and lower range limits as being the same as those of the primary variable. It is possible to assign the analog output to other sources, but other assignments are non-standard, and the units displayed by the remote system will not be correct. Teledyne Analytical Instruments 39

40 Operation LXT-220 DO If the 4-20 selected for the HART analog output is assigned to missing or unused then the digital representation of the output current will be not a number, but with up to four digital variables still being transmitted Relay Assignments The next 8 displays are for the relay assignments. The first of the relay displays is: Relay 1:... Where... represents an item from the same list that is used for the 4-20 assignments. The procedure for selecting a relay assignment is the same as for the 4-20 outputs. See Section mA Output Assignments. Up to two relays can be assigned to the same source, so one relay can be used to control the process, and another relay can be used as an alarm if the process value is out of limits. The relay configuration menu provides for 8 relays, but most units do not have that many relays installed. Some units do not have any relays installed, but the relay menu will nevertheless be present as the relays can be retrofitted. The software cannot determine how many relays are actually present, so the missing selection might not reflect the actual configuration. A display showing the relay setpoints for each relay is present in the main menu. If the relay is assigned to a channel 2 function then the display will be in the channel 2 group. The display is not shown if the missing or unused selection is made. A new relay assignment is not necessarily functional until the setpoints in the span display are set. If a PID controller is selected as a source then its support displays will also be present Temperature Calibration The next display is for calibrating the process temperature displayed by the instrument. Trim O C.0 Unit 25.0 O C Temperature Calibration Teledyne Analytical Instruments 40